Mild photo-thermal microneedle patch as well as preparation method and application thereof

Abstract

The invention relates to the technical field of pharmaceutical preparations, and discloses a mild photo-thermal microneedle patch and a preparation method and application thereof, and the mild photo-thermal microneedle patch comprises a substrate and needle tips arranged on the substrate in an array; the substrate is prepared from the following raw materials in parts by weight: 400 to 500 parts of N-isopropylacrylamide, 30.5 to 40.5 parts of acrylamide, 4 to 5 parts of polydopamine nanoparticles, 10 to 30 parts of N, N-methylene bisacrylamide, 100 to 200 parts of sodium alginate, 6.2 to 9.3 parts of tetramethylethylenediamine and 8 to 12 parts of potassium persulfate; the needle tip is prepared from the following raw materials in parts by weight: 0.1 to 0.5 part of methacrylated gelatin, 0.2 to 0.6 part of deferoxamine mesylate, 0.8 to 1.2 parts of a photoinitiator and 33.6 to 56 parts of polyethylene glycol diacrylate. The mild photo-thermal microneedle patch can realize photo-thermal sterilization under near-infrared irradiation, and also can promote skin repair and regeneration.

Description

Technical Field

[0001] The present invention belongs to the technical field of pharmaceutical preparations, and in particular relates to a mild photothermal microneedle patch and a preparation method and application thereof. Background Art

[0002] Traditional skin dressings, such as poultices and ointments, can cause skin allergies and other intolerance reactions when used on skin wounds for a long time. Solid gauze dressings, for example, have no positive effect on wound healing and are inconvenient to replace. The development of sprays and aerosols is also limited by their stringent requirements for drugs and high costs. In addition, general dressings only act on the surface of the skin, and due to the obstruction of the skin structure, it is difficult for the active ingredients to penetrate, so the effect is also poor.

[0003] Microneedles (MNs) are a new type of injection that replaces traditional needles. They can not only reduce the pain and fear of drug administration, but also more effectively deliver drugs percutaneously and intradermally / collect samples. Chinese patent CN 113069683B discloses a method for preparing a soluble microneedle patch for wound repair, which is prepared by polydimethylsiloxane mold replication and ultraviolet light curing, with methacrylated hyaluronic acid, polyethylene glycol diacrylate or methacrylated gelatin as the main ingredients.

[0004] This microneedle patch only promotes wound healing through the methacrylated hyaluronic acid or methacrylated gelatin in the raw materials, but does not enhance the bactericidal effect. Summary of the invention

[0005] The present invention provides a mild photothermal microneedle patch and a preparation method and application thereof, which solves the problem that the microneedle patch prepared in the prior art only promotes wound healing through methacrylated hyaluronic acid or methacrylated gelatin in the raw materials but does not improve the bactericidal effect.

[0006] The first aspect of the present invention provides a mild photothermal microneedle patch, which comprises a substrate and needle tips arranged in an array on the substrate;

[0007] The raw materials of the substrate include, by weight: 400-500 parts of N-isopropyl acrylamide, 30.5-40.5 parts of acrylamide, 4-5 parts of polydopamine nanoparticles, 10-30 parts of N,N-methylenebisacrylamide, 100-200 parts of sodium alginate, 6.2-9.3 parts of tetramethylethylenediamine, and 8-12 parts of potassium persulfate;

[0008] The raw materials of the needle tip include, by weight: 0.1 to 0.5 parts of methacrylated gelatin, 0.2 to 0.6 parts of deferoxamine mesylate, 0.8 to 1.2 parts of a photoinitiator, and 33.6 to 56 parts of polyethylene glycol diacrylate.

[0009] Preferably, the raw materials of the substrate include, by weight: 430-470 parts of N-isopropyl acrylamide, 33.5-38.5 parts of acrylamide, 4-5 parts of polydopamine nanoparticles, 15-25 parts of N,N-methylenebisacrylamide, 130-170 parts of sodium alginate, 6.975-8.525 parts of tetramethylethylenediamine, and 9-11 parts of potassium persulfate;

[0010] The raw materials of the needle tip include, by weight: 0.2 to 0.4 parts of methacrylated gelatin, 0.3 to 0.5 parts of deferoxamine mesylate, 0.9 to 1.1 parts of a photoinitiator, and 39.2 to 50.4 parts of polyethylene glycol diacrylate.

[0011] Preferably, the raw materials of the substrate include, by weight: 450 parts of N-isopropylacrylamide, 37.5 parts of acrylamide, 4 parts of polydopamine nanoparticles, 20 parts of N,N-methylenebisacrylamide, 150 parts of sodium alginate, 7.75 parts of tetramethylethylenediamine, and 10 parts of potassium persulfate;

[0012] The raw materials of the needle tip include, by weight: 0.3 parts of methacrylated gelatin, 0.4 parts of deferoxamine mesylate, 1 part of photoinitiator, and 44.8 parts of polyethylene glycol diacrylate.

[0013] Preferably, the photoinitiator is phenyl-2,4,6-trimethylbenzoylphosphite lithium salt.

[0014] The second object of the present invention is to protect the preparation method of the mild photothermal microneedle patch, comprising:

[0015] Preparation of needle tip: dissolving the formulated amount of methacrylated gelatin and deferoxamine mesylate, adding the formulated amount of photoinitiator and polyethylene glycol diacrylate at 50-60° C. to obtain a mixed solution; casting the mixed solution onto a PDMS mold, centrifuging it, and irradiating it with blue light for 30 seconds to obtain the needle tip;

[0016] Preparation of the substrate: dissolving the formulated amount of poly (N-isopropylacrylamide), acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles, adding tetramethylethylenediamine and potassium persulfate to obtain a substrate solution, and then allowing the obtained substrate solution to stand until it is completely polymerized to obtain the substrate;

[0017] The needle tip and the substrate are subjected to a microneedle molding process to obtain the mild photothermal microneedle patch.

[0018] Preferably, in the preparation of the needle tip, the centrifugation condition is 3000 rpm for 5 min.

[0019] Preferably, the microneedle forming process comprises:

[0020] The needle tip is cast on a PDMS template, and after centrifugation, the substrate is added to completely cover the needle tip, and after standing to form a gel, it is dried and demoulded to obtain the mild photothermal microneedle patch.

[0021] Preferably, the preparation method of the polydopamine nanoparticles is:

[0022] adding aqueous ammonia to a mixed solution of ethanol and water to obtain a mixed solution;

[0023] Dopamine hydrochloride is added to the mixed solution, and the mixture is reacted for 24 hours in the dark to obtain the polydopamine nanoparticles.

[0024] Preferably, the ratio of ammonia water, ethanol, water and dopamine hydrochloride is 1 mL:40 mL:100 mL:500 mg.

[0025] The third object of the present invention is to protect the use of the mild photothermal microneedle patch in the preparation of chronic wound repair dressings.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The mild photothermal microneedle patch provided by the present invention is prepared by compounding methacrylated gelatin, deferoxamine mesylate, a photoinitiator, polyethylene glycol diacrylate, N-isopropylacrylamide, acrylamide, polydopamine nanoparticles, N,N-methylenebisacrylamide, sodium alginate, tetramethylethylenediamine, and potassium persulfate. On the one hand, the mild photothermal microneedle patch can achieve photothermal sterilization under near-infrared irradiation, and the mild photothermal microneedle patch can achieve a temperature control effect within the range of mild photothermal, and can provide more effective protection for healthy tissues compared with photothermal therapy; on the other hand, the mild photothermal microneedle patch has a strong network structure, can better adsorb and retain deferoxamine mesylate, and has a low degradation rate, and slowly releases the angiogenesis-promoting drug deferoxamine mesylate, which plays a role in repairing the proliferation period for the angiogenesis problem of chronic diabetic wounds in the proliferation period, and can also promote skin repair and regeneration, avoiding the potential harm caused by the use of antibiotics. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 SEM characterization of PDA NPs prepared in Example 1;

[0029] Figure 2 Verification of the photothermal performance of PDA NPs prepared in Example 1;

[0030] Figure 3 This is a SEM image of the mild photothermal microneedle patch prepared in Example 1;

[0031] Figure 4 This is a thermal image of the mild photothermal microneedle patch prepared in Example 1;

[0032] Figure 5 Plating results for different groups of bacteria;

[0033] Figure 6 Stain different groups of bacteria for live or dead status. DETAILED DESCRIPTION

[0034] The technical solutions in the present invention will be described clearly and completely below in conjunction with the specific implementation of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] The methods described in the embodiments of the present invention are conventional methods unless otherwise specified. The materials, reagents, etc. used can be obtained from commercial sources unless otherwise specified.

[0036] In the following description of this embodiment, the term "and / or" is used to describe the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, B exists alone, and A and B exist at the same time. Among them, A and B can be singular or plural; the single symbol " / " means "or".

[0037] In the following description of this embodiment, the term "at least one" refers to one or more, and "plurality" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, "at least one of A, B or C", or "at least one of A, B and C" can represent any one of A, B, C, or A+B, or A+C, or B+C, or A+B+C, where A, B, C can be single or multiple, respectively.

[0038] In the following description of this embodiment, the order of serial numbers does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of this embodiment.

[0039] In the following description of the present embodiment, the numerical range should be understood to also specifically disclose each intermediate value between the upper and lower limits of the range. Any stated value or intermediate value in the stated range and any other stated value or each smaller range between the intermediate values ​​in the stated range are also included in the present embodiment, and the upper and lower limits of the smaller range can be independently included or excluded in the range.

[0040] Unless otherwise stated, the technical / scientific terms used in the present embodiment have the same meanings as those generally understood by those skilled in the art to which the present application belongs. Although the present application only describes preferred methods and materials, any similar or equivalent methods and materials may also be used in the implementation or testing of the present application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of any conflict with any incorporated document, the content of this specification shall prevail.

[0041] Abbreviations of some substances in the examples and comparative examples of the present invention:

[0042] N-isopropylacrylamide: NIPAM, acrylamide: AM, polydopamine nanoparticles PDA NPs, methacryloyl gelatin: GelMA, deferoxamine mesylate: DFO, polyethylene glycol diacrylate: PEGDA, N,N-methylenebisacrylamide: MBA, tetramethylethylenediamine: TEMED, potassium persulfate: KPS, phenyl-2,4,6-trimethylbenzoylphosphite lithium salt: LAP.

[0043] Example 1

[0044] A mild photothermal microneedle patch, comprising a substrate and needle tips arranged in an array on the substrate;

[0045] The raw materials of the substrate include, by weight: 400 parts of N-isopropyl acrylamide, 30.5 parts of acrylamide, 4 parts of polydopamine nanoparticles, 10 parts of N,N-methylenebisacrylamide, 100 parts of sodium alginate, 6.2 parts of tetramethylethylenediamine, and 8 parts of potassium persulfate;

[0046] The raw materials of the needle tip include, by weight: 0.1 parts of methacrylated gelatin, 0.2 parts of deferoxamine mesylate, 0.8 parts of photoinitiator, and 33.6 parts of polyethylene glycol diacrylate.

[0047] A method for preparing a mild photothermal microneedle patch, comprising:

[0048] (1) Preparation of polydopamine nanoparticles

[0049] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0050] A dopamine hydrochloride solution with a concentration of 50 mg / mL was prepared, 10 mL of the dopamine hydrochloride solution was added dropwise to the mixed solution, the mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0051] (2) Preparation of needle tip: Dissolve the formulated amount of methacrylated gelatin and deferoxamine mesylate in 2 mL of deionized water at 50°C, add phenyl-2,4,6-trimethylbenzoylphosphite lithium salt at 60°C, add polyethylene glycol diacrylate, mix well, cast on a PDMS mold, and centrifuge at 3000 rpm for 5 minutes. Expose the filled mold to blue light (405 nm) for 30 seconds to obtain the needle tip.

[0052] (3) Preparation of substrate: Dissolve the formulated amounts of N-isopropylacrylamide, acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles in 5 mL of water and stir to obtain a homogeneous solution; add the formulated amounts of tetramethylethylenediamine and potassium persulfate to the homogeneous solution while continuously stirring to obtain a substrate solution; then mix the obtained substrate solution evenly and let it stand at room temperature for 24 hours to allow it to completely polymerize and form a gel, thereby obtaining the substrate.

[0053] (4) Casting the needle tip on the PDMS template, centrifuging at a speed of 3000 r / min for 5 min to fully fill the cavity of the template, scraping off the excess needle tip liquid on the surface of the PDMS mold after the centrifugation; then adding the substrate to completely cover the needle tip, leaving it to stand at room temperature to form a gel, drying it in a drying oven at 25° C. for 24 h, and demolding to obtain a mild photothermal microneedle patch, which is recorded as

[0054] GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN, abbreviated as NSA@PDA-GPD.

[0055] Example 2

[0056] A mild photothermal microneedle patch, comprising a substrate and needle tips arranged in an array on the substrate;

[0057] The raw materials of the substrate include, by weight: 430 parts of N-isopropyl acrylamide, 33.5 parts of acrylamide, 4 parts of polydopamine nanoparticles, 15 parts of N,N-methylenebisacrylamide, 130 parts of sodium alginate, 6.975 parts of tetramethylethylenediamine, and 9 parts of potassium persulfate;

[0058] The raw materials of the needle tip include, by weight: 0.2 parts of methacrylated gelatin, 0.3 parts of deferoxamine mesylate, 0.9 parts of photoinitiator, and 39.2 parts of polyethylene glycol diacrylate.

[0059] A method for preparing a mild photothermal microneedle patch, comprising:

[0060] (1) Preparation of polydopamine nanoparticles

[0061] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0062] A dopamine hydrochloride solution with a concentration of 50 mg / mL was prepared, 10 mL of the dopamine hydrochloride solution was added dropwise to the mixed solution, the mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0063] (2) Preparation of needle tip: Dissolve the formulated amount of methacrylated gelatin and deferoxamine mesylate in 2 mL of deionized water at 50° C., add phenyl-2,4,6-trimethylbenzoylphosphinate lithium salt at 60° C., add the formulated amount of polyethylene glycol diacrylate, mix well, cast on a PDMS mold, and centrifuge at 3000 rpm for 5 min. Expose the filled mold to blue light (405 nm) for 30 s to obtain the needle tip.

[0064] (3) Preparation of substrate: Dissolve the formulated amounts of N-isopropylacrylamide, acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles in 5 mL of water and stir to obtain a homogeneous solution; add the formulated amounts of tetramethylethylenediamine and potassium persulfate to the homogeneous solution while continuously stirring to obtain a substrate solution; then mix the obtained substrate solution evenly and pour it into a mold filled with a needle tip, and let it stand at room temperature for 24 hours to allow it to completely polymerize and form a gel to obtain the substrate.

[0065] (4) Casting the needle tip on the PDMS template, centrifuging at a speed of 3000 r / min for 5 min to fully fill the cavity of the template, scraping off the excess needle tip liquid on the surface of the PDMS mold after the centrifugation; then adding the substrate to completely cover the needle tip, leaving it to stand at room temperature to form a gel, drying it in a drying oven at 25° C. for 24 h, and demolding to obtain a mild photothermal microneedle patch, which is recorded as

[0066] GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN, abbreviated as NSA@PDA-GPD.

[0067] Example 3

[0068] A mild photothermal microneedle patch, comprising a substrate and needle tips arranged in an array on the substrate;

[0069] The raw materials of the substrate include, by weight: 450 parts of N-isopropyl acrylamide, 37.5 parts of acrylamide, 5 parts of polydopamine nanoparticles, 20 parts of N,N-methylenebisacrylamide, 150 parts of sodium alginate, 7.75 parts of tetramethylethylenediamine, and 10 parts of potassium persulfate;

[0070] The raw materials of the needle tip include, by weight: 0.3 parts of methacrylated gelatin, 0.4 parts of deferoxamine mesylate, 1 part of photoinitiator, 44.8 parts of polyethylene glycol diacrylate

[0071] A method for preparing a mild photothermal microneedle patch, comprising:

[0072] (1) Preparation of polydopamine nanoparticles

[0073] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0074] A dopamine hydrochloride solution with a concentration of 50 mg / mL was prepared, 10 mL of the dopamine hydrochloride solution was added dropwise to the mixed solution, the mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0075] (2) Preparation of needle tip: Dissolve the formulated amount of methacrylated gelatin and deferoxamine mesylate in 2 mL of deionized water at 50° C., and add the formulated amount of phenyl-2,4,6-trimethylbenzoylphosphinate lithium salt and polyethylene glycol diacrylate at 60° C., mix well, cast on a PDMS mold, and centrifuge at 3000 rpm for 5 min. Expose the filled mold to blue light (405 nm) for 30 s to obtain the needle tip.

[0076] (3) Preparation of substrate: Dissolve the formulated amounts of N-isopropylacrylamide, acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles in 5 mL of water and stir to obtain a homogeneous solution; add the formulated amounts of tetramethylethylenediamine and potassium persulfate to the homogeneous solution while continuously stirring to obtain a substrate solution; then mix the obtained substrate solution evenly and let it stand at room temperature for 24 hours to allow it to completely polymerize and form a gel, thereby obtaining the substrate.

[0077] (4) Casting the needle tip on the PDMS template, centrifuging at a speed of 3000 r / min for 5 min to fully fill the cavity of the template, scraping off the excess needle tip liquid on the surface of the PDMS mold after the centrifugation; then adding the substrate to completely cover the needle tip, leaving it to stand at room temperature to form a gel, drying it in a drying oven at 20° C. for 24 h, and demolding to obtain a mild photothermal microneedle patch, which is recorded as

[0078] GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN, abbreviated as NSA@PDA-GPD.

[0079] Example 4

[0080] A mild photothermal microneedle patch, comprising a substrate and needle tips arranged in an array on the substrate;

[0081] The raw materials of the substrate include, by weight: 470 parts of N-isopropyl acrylamide, 38.5 parts of acrylamide, 4 parts of polydopamine nanoparticles, 25 parts of N,N-methylenebisacrylamide, 170 parts of sodium alginate, 8.525 parts of tetramethylethylenediamine, and 11 parts of potassium persulfate;

[0082] The raw materials of the needle tip include, by weight: 0.4 parts of methacrylated gelatin, 0.5 parts of deferoxamine mesylate, 1.1 parts of photoinitiator, and 50.4 parts of polyethylene glycol diacrylate.

[0083] A method for preparing a mild photothermal microneedle patch, comprising:

[0084] (1) Preparation of polydopamine nanoparticles

[0085] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0086] A dopamine hydrochloride solution with a concentration of 50 mg / mL was prepared, 10 mL of the dopamine hydrochloride solution was added dropwise to the mixed solution, the mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0087] (2) Preparation of needle tip: Dissolve the formulated amount of methacrylated gelatin and deferoxamine mesylate in 2 mL of deionized water at 50° C., and add the formulated amount of phenyl-2,4,6-trimethylbenzoylphosphinate lithium salt and polyethylene glycol diacrylate at 60° C., mix well, cast on a PDMS mold, and centrifuge at 3000 rpm for 5 min. Expose the filled mold to blue light (405 nm) for 30 s to obtain the needle tip.

[0088] (3) Preparation of substrate: Dissolve the formulated amounts of N-isopropylacrylamide, acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles in 5 mL of water and stir to obtain a homogeneous solution; add the formulated amounts of tetramethylethylenediamine and potassium persulfate to the homogeneous solution while continuously stirring to obtain a substrate solution; then mix the obtained substrate solution evenly and let it stand at room temperature for 24 hours to allow it to completely polymerize and form a gel, thereby obtaining the substrate.

[0089] (4) Casting the needle tip on the PDMS template, centrifuging at a speed of 3000 r / min for 5 min to fully fill the cavity of the template, scraping off the excess needle tip liquid on the surface of the PDMS mold after the centrifugation; then adding the substrate to completely cover the needle tip, leaving it to stand at room temperature to form a gel, drying it in a drying oven at 25° C. for 24 h, and demolding to obtain a mild photothermal microneedle patch, which is recorded as

[0090] GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN, abbreviated as NSA@PDA-GPD.

[0091] Example 5

[0092] A mild photothermal microneedle patch, comprising a substrate and needle tips arranged in an array on the substrate;

[0093] The raw materials of the substrate include, by weight: 500 parts of N-isopropyl acrylamide, 40.5 parts of acrylamide, 4 parts of polydopamine nanoparticles, 30 parts of N,N-methylenebisacrylamide, 200 parts of sodium alginate, 9.3 parts of tetramethylethylenediamine, and 12 parts of potassium persulfate;

[0094] The raw materials of the needle tip include, by weight: 0.5 parts of methacrylated gelatin, 0.6 parts of deferoxamine mesylate, 1.2 parts of photoinitiator, and 56 parts of polyethylene glycol diacrylate.

[0095] A method for preparing a mild photothermal microneedle patch, comprising:

[0096] (1) Preparation of polydopamine nanoparticles

[0097] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0098] A dopamine hydrochloride solution with a concentration of 50 mg / mL was prepared, 10 mL of the dopamine hydrochloride solution was added dropwise to the mixed solution, the mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0099] (2) Preparation of needle tip: Dissolve the formulated amount of methacrylated gelatin and deferoxamine mesylate in 2 mL of deionized water at 50° C., and add the formulated amount of phenyl-2,4,6-trimethylbenzoylphosphinate lithium salt and polyethylene glycol diacrylate at 60° C., mix well, cast on a PDMS mold, and centrifuge at 3000 rpm for 5 min. Expose the filled mold to blue light (405 nm) for 30 s to obtain the needle tip.

[0100] (3) Preparation of substrate: Dissolve the formulated amounts of N-isopropylacrylamide, acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles in 5 mL of water and stir to obtain a homogeneous solution; add the formulated amounts of tetramethylethylenediamine and potassium persulfate to the homogeneous solution while continuously stirring to obtain a substrate solution; then mix the obtained substrate solution evenly and let it stand at room temperature for 24 hours to allow it to completely polymerize and form a gel, thereby obtaining the substrate.

[0101] (4) Casting the needle tip on the PDMS template, centrifuging at a speed of 3000 r / min for 5 min to fully fill the cavity of the template, scraping off the excess needle tip liquid on the surface of the PDMS mold after the centrifugation; then adding the substrate to completely cover the needle tip, leaving it to stand at room temperature to form a gel, drying it in a drying oven at 25° C. for 24 h, and demolding to obtain a mild photothermal microneedle patch, which is recorded as

[0102] GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN, abbreviated as NSA@PDA-GPD.

[0103] Comparative Example 1

[0104] A method for preparing a microneedle patch, comprising:

[0105] 0.3 g of methacrylated gelatin was dissolved in 2 mL of deionized water at 50°C, and 1 mg of photoinitiator was added at 60°C, 40 μL of polyethylene glycol diacrylate was added, mixed evenly, cast on a PDMS mold, and centrifuged at 3000 rpm for 5 min. The filled mold was exposed to blue light (405 nm) for 30 s to obtain the microneedle patch, which was recorded as GelMA-PEGDA MN, abbreviated as GP.

[0106] Comparative Example 2

[0107] A method for preparing a microneedle patch, comprising:

[0108] 0.3 g of methacrylated gelatin and 0.4 mg of deferoxamine mesylate were dissolved in 2 mL of deionized water at 50 ° C, and 1 mg of photoinitiator was added at 60 ° C, and 40 μL of polyethylene glycol diacrylate was added, mixed evenly, cast on a PDMS mold and centrifuged at 3000 rpm for 5 min. The filled mold was exposed to blue light (405 nm) for 30 s to obtain the microneedle patch, which was recorded as GelMA-PEGDA@DFO MN, abbreviated as G / P@D.

[0109] Comparative Example 3

[0110] A method for preparing a microneedle patch, comprising:

[0111] 450 mg of N-isopropylacrylamide, 37.5 mg of acrylamide, 20 mg of N,N-methylenebisacrylamide, and 150 mg of sodium alginate were dissolved in 5 mL of water and stirred to obtain a homogeneous solution; under continuous stirring, 10 μL of tetramethylethylenediamine and 10 mg of potassium persulfate were added to the homogeneous solution, mixed evenly, and poured into a mold filled with needle tips, and allowed to stand at room temperature for 24 hours to allow it to completely polymerize and form a gel, thereby obtaining the microneedle patch, which was recorded as NIPAM-AM-SA MN, abbreviated as NSA.

[0112] Comparative Example 4

[0113] A method for preparing a microneedle patch, comprising:

[0114] 450 mg of N-isopropylacrylamide, 37.5 mg of acrylamide, 20 mg of N,N-methylenebisacrylamide, 150 mg of sodium alginate, and 4 mg of polydopamine nanoparticles were dissolved in 5 mL of water and stirred to obtain a homogeneous solution; under continuous stirring, 10 μL of tetramethylethylenediamine and 10 mg of potassium persulfate were added to the homogeneous solution, mixed evenly, and poured into a mold filled with needle tips, and allowed to stand at room temperature for 24 hours to allow it to completely polymerize and form a gel, thereby obtaining the microneedle patch, recorded as NIPAM-AM-SA@PDA MN, abbreviated as NSA@PDA.

[0115] Comparative Example 5

[0116] A method for preparing a mild photothermal microneedle patch, comprising:

[0117] (1) Preparation of polydopamine nanoparticles

[0118] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0119] A dopamine hydrochloride solution with a concentration of 50 mg / mL was prepared and added dropwise to the mixed solution. The mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0120] (2) Preparation of needle tip: 0.3 g of methacrylated gelatin and 0.4 mg of deferoxamine mesylate were dissolved in 2 mL of deionized water at 50° C., and 1 mg of phenyl-2,4,6-trimethylbenzoylphosphinate lithium salt was added at 60° C., and 40 μL of polyethylene glycol diacrylate was added. After mixing well, the mixture was cast onto a PDMS mold and centrifuged at 3000 rpm for 5 min. The filled mold was exposed to blue light (405 nm) for 30 s to obtain the needle tip.

[0121] (3) Preparation of substrate: 450 mg of N-isopropylacrylamide, 40.9 mg of acrylamide, 20 mg of N,N-methylenebisacrylamide, 150 mg of sodium alginate, and 4 mg of polydopamine nanoparticles were dissolved in 5 mL of water and stirred to obtain a homogeneous solution; while continuously stirring, 10 μL of tetramethylethylenediamine and 10 mg of potassium persulfate were added to the homogeneous solution, mixed evenly, and poured into a mold filled with a needle tip, and allowed to stand at room temperature for 24 h to allow it to completely polymerize and form a gel, thereby obtaining the substrate.

[0122] (4) Casting the needle tip on the PDMS template and centrifuging at a speed of 3000 r / min for 5 min to fully fill the cavity of the template. After the centrifugation, scrape off the excess needle tip liquid on the surface of the PDMS mold; then add the substrate to completely cover the needle tip, let it stand at room temperature to form a gel, and then dry it in a drying oven at 25°C for 24 h. Demolding to obtain a mild photothermal microneedle patch, recorded as NIPAM:AM=11:1.

[0123] Comparative Example 6

[0124] A method for preparing a mild photothermal microneedle patch, comprising:

[0125] (1) Preparation of polydopamine nanoparticles

[0126] Under magnetic stirring, 1 mL of aqueous ammonia was added to 40 mL of ethanol and 90 mL of reverse osmosis water to obtain a mixed solution.

[0127] A dopamine hydrochloride solution with a concentration of 50 / mL was prepared and added dropwise to the mixed solution. The mixture was reacted for 24 hours in the dark, and then washed and dried to obtain polydopamine nanoparticles.

[0128] (2) Preparation of needle solution: 0.3 g of methacrylated gelatin and 0.4 mg of deferoxamine mesylate were dissolved in 2 mL of deionized water at 50°C, and 1 mg of phenyl-2,4,6-trimethylbenzoylphosphinate lithium salt was added at 60°C, and 40 μL of polyethylene glycol diacrylate was added. After mixing well, the mixture was cast onto a PDMS mold and centrifuged at 3000 rpm for 5 min. The filled mold was exposed to blue light (405 nm) for 30 s.

[0129] (3) Preparation of substrate: 450 mg of N-isopropylacrylamide, 34.62 mg of acrylamide, 20 mg of N,N-methylenebisacrylamide, 150 mg of sodium alginate, and 4 mg of polydopamine nanoparticles were dissolved in 5 mL of water and stirred to obtain a homogeneous solution; while continuously stirring, 10 μL of tetramethylethylenediamine and 10 mg of potassium persulfate were added to the homogeneous solution, mixed evenly, and poured into a mold filled with a needle tip, and allowed to stand at room temperature for 24 h to allow it to completely polymerize and form a gel, thereby obtaining the substrate.

[0130] (4) Cast the needle tip on the PDMS template and centrifuge at a speed of 3000 r / min for 5 min to fully fill the cavity of the template. After centrifugation, scrape off the excess needle tip liquid on the surface of the PDMS mold; then add the substrate to completely cover the needle tip, let it stand at room temperature to form a gel, and then dry it in a drying oven at 25°C for 24 h. Demolding to obtain a mild photothermal microneedle patch, recorded as NIPAM:AM=13:1.

[0131] Performance Test:

[0132] 1. Figure 1 This is the SEM image of the polydopamine nanoparticles prepared in Example 1.

[0133] 2. Figure 2 The photothermal performance diagram of polydopamine nanoparticles prepared in Example 1. In order to avoid excessive amounts of nanoparticles from being toxic to cells and to ensure that the material still has a good heating effect under low-power near-infrared irradiation, the photothermal performance of dopamine nanoparticles of different concentrations was verified. It was found that with the increase of dopamine nanoparticle concentration, the heating rate and the final temperature also increased. Figure 2 (a); 600 μg / ml dopamine nanoparticles were selected for heating experiments under near-infrared irradiation of different powers, and the heating curves were obtained as shown in Figure 2 (b), 800 μg / ml of dopamine nanoparticles was selected as the final concentration in subsequent experiments.

[0134] 3. Figure 3 This is a morphology picture of the mild photothermal microneedle patch prepared in Example 1.

[0135] 4. Verification of NIPAM-AM-SA temperature control performance:

[0136] The mild photothermal microneedle patch prepared in Example 1 and the mild photothermal microneedle patches prepared in Comparative Examples 5 and 6 were subjected to near-infrared light irradiation. Figure 4 The thermal images of different groups verify that NIPAM-AM-SA can change the LCST of the material by adjusting the ratio of NIPAM and AM, so that the temperature can be controlled within the ideal temperature range. The mild photothermal microneedle patch prepared in Example 1 can control the temperature within the mild photothermal temperature range.

[0137] 5. Antibacterial properties

[0138] A quarter of a microneedle was placed in each well of a 24-well plate. The groups were: blank, GelMA-PEGDA MN, GelMA-PEGDA@DFO MN, NIPAM-AM-SA MN, NIPAM-AM-SA@PDA MN, and GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN. They were divided into a light group and a dark group. After adding 900 μL of liquid culture medium to each well, 100 μL of 10 6 CFU mL -1 Escherichia coli, denoted as E., and Staphylococcus aureus, denoted as S., were incubated in the light-proof condition for 40 minutes and then irradiated with near-infrared light for 10 minutes. 100 μL of each group was taken for plating; the dark group was incubated in the dark-proof condition for 50 minutes and then 100 μL of each group was taken for plating. After plating, the solid culture medium was placed in a bacterial incubator for 12 hours and then taken out for observation.

[0139] The results showed that: under near-infrared irradiation, no bacteria grew on the solid culture medium surface of the mild photothermal microneedle patch prepared in Example 1, while obvious colony growth was observed on the solid culture medium surface of the microneedle patch prepared in other control groups; without near-infrared irradiation, obvious colony growth was observed on the solid culture medium surface of the mild photothermal microneedle patch prepared in Example 1 and the solid culture medium surface of the microneedle patch prepared in other control groups. Figure 5 .

[0140] 6. Verification of antibacterial mechanism

[0141] Live / dead bacteria staining was used to verify the antimicrobial mechanism.

[0142] The groups were: blank, GelMA-PEGDA MN, GelMA-PEGDA@DFO MN, NIPAM-AM-SA MN, NIPAM-AM-SA@PDA MN,

[0143] GelMA-PEGDA@DFO+NIPAM-AM-SA@PDA MN.

[0144] coli and Staphylococcus aureus (100 μL, 10 6 CFU mL -1 ) were co-cultured at 37°C for 6 h, and live / dead bacteria were stained with SYTO 9 and PI in the dark. Finally, the cells were observed and photographed under a laser confocal microscope.

[0145] The results showed that: under near-infrared irradiation, a large number of dead bacteria appeared on the solid culture medium surface of the mild photothermal microneedle patch prepared in Example 1, while obvious colony growth appeared on the solid culture medium surface of the microneedle patch prepared in other control groups; without near-infrared irradiation, obvious colony growth appeared on the solid culture medium surface of the mild photothermal microneedle patch prepared in Example 1 and the solid culture medium surface of the microneedle patch prepared in other control groups, as shown in FIG. Figure 6 The mild photothermal microneedle patch prepared in Example 1 can achieve photothermal sterilization under near-infrared irradiation.

[0146] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0147] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A mild photothermal microneedle patch, characterized in that: The method comprises a substrate and needle tips arranged in an array on the substrate; The raw materials of the substrate include, by weight: 400-500 parts of N-isopropyl acrylamide, 30.5-40.5 parts of acrylamide, 4-5 parts of polydopamine nanoparticles, 10-30 parts of N,N-methylenebisacrylamide, 100-200 parts of sodium alginate, 6.2-9.3 parts of tetramethylethylenediamine, and 8-12 parts of potassium persulfate; The raw materials of the needle tip include, by weight: 0.1 to 0.5 parts of methacrylated gelatin, 0.2 to 0.6 parts of deferoxamine mesylate, 0.8 to 1.2 parts of a photoinitiator, and 33.6 to 56 parts of polyethylene glycol diacrylate.

2. The mild photothermal microneedle patch according to claim 1, characterized in that: The raw materials of the substrate include, by weight: 430-470 parts of N-isopropyl acrylamide, 33.5-38.5 parts of acrylamide, 4-5 parts of polydopamine nanoparticles, 15-25 parts of N,N-methylenebisacrylamide, 130-170 parts of sodium alginate, 6.975-8.525 parts of tetramethylethylenediamine, and 9-11 parts of potassium persulfate; The raw materials of the needle tip include, by weight: 0.2 to 0.4 parts of methacrylated gelatin, 0.3 to 0.5 parts of deferoxamine mesylate, 0.9 to 1.1 parts of a photoinitiator, and 39.2 to 50.4 parts of polyethylene glycol diacrylate.

3. The mild photothermal microneedle patch according to claim 2, characterized in that: The raw materials of the substrate include, by weight: 450 parts of N-isopropyl acrylamide, 37.5 parts of acrylamide, 4 parts of polydopamine nanoparticles, 20 parts of N,N-methylenebisacrylamide, 150 parts of sodium alginate, 7.75 parts of tetramethylethylenediamine, and 10 parts of potassium persulfate; The raw materials of the needle tip include, by weight: 0.3 parts of methacrylated gelatin, 0.4 parts of deferoxamine mesylate, 1 part of photoinitiator, and 44.8 parts of polyethylene glycol diacrylate.

4. The mild photothermal microneedle patch according to any one of claims 1 to 3, characterized in that: The photoinitiator is phenyl-2,4,6-trimethylbenzoyl phosphite lithium salt.

5. The method for preparing a mild photothermal microneedle patch according to claim 1, characterized in that: Include: Preparation of needle tip: dissolving the formulated amount of methacrylated gelatin and deferoxamine mesylate, adding the formulated amount of photoinitiator and polyethylene glycol diacrylate at 50-60° C. to obtain a mixed solution; casting the mixed solution onto a PDMS mold, centrifuging it, and irradiating it with blue light for 30 seconds to obtain the needle tip; Preparation of the substrate: dissolving the formulated amount of N-isopropylacrylamide, acrylamide, N,N-methylenebisacrylamide, sodium alginate, and polydopamine nanoparticles, adding tetramethylethylenediamine and potassium persulfate to obtain a substrate solution, and then allowing the obtained substrate solution to stand until it is completely polymerized to obtain the substrate; The needle tip and the substrate are subjected to a microneedle molding process to obtain the mild photothermal microneedle patch.

6. The method for preparing the mild photothermal microneedle patch according to claim 5, characterized in that: In the preparation of the needle tip, the centrifugation condition is 3000 rpm for 5 minutes.

7. The method for preparing the mild photothermal microneedle patch according to claim 5, characterized in that: The microneedle forming process comprises: The needle tip is cast on a PDMS template, and after centrifugation, the substrate is added to completely cover the needle tip, and after standing to form a gel, it is dried and demoulded to obtain the mild photothermal microneedle patch.

8. The method for preparing the mild photothermal microneedle patch according to claim 5, characterized in that: The preparation method of the polydopamine nanoparticles is: adding aqueous ammonia to a mixed solution of ethanol and water to obtain a mixed solution; Dopamine hydrochloride is added to the mixed solution, and the mixture is reacted for 24 hours in the dark to obtain the polydopamine nanoparticles.

9. The method for preparing the mild photothermal microneedle patch according to claim 8, characterized in that: The ratio of ammonia water, ethanol, water, and dopamine hydrochloride is 1mL:40mL:100mL:500mg.

10. Use of the mild photothermal microneedle patch according to claim 9 in preparing a chronic wound repair dressing.

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